1. Field of the Invention
The present invention relates to a Plasma Display Panel (PDP), and more particularly, to a PDP having a high aperture ratio of a discharge cell, a high light transmittance, and a high luminous efficiency and in which a stable and efficient discharge occurs uniformly at a low driving voltage on inner sidewalls of the discharge cell and concentrates in the center of the discharge cell.
2. Description of the Related Art
In an AC, triode-type, surface discharge PDP, the PDP comprises a front panel and a rear panel. The front panel comprises a front substrate, pairs of sustain electrodes composed of Y electrodes and X electrodes on a rear surface of the front substrate, a front dielectric layer covering the sustain electrodes, and a protective layer covering the front dielectric layer. Each of the Y electrodes is composed of a transparent electrode and a bus electrode, and each of the X electrodes is composed of a transparent electrode and a bus electrode. The transparent electrodes are made of Indium Tin Oxide (ITO) or the like. The bus electrodes are connected to connection cables (not shown) disposed at right and left sides of the PDP.
The rear panel comprises a rear substrate, address electrodes disposed on a front surface of the rear substrate and intersecting the pairs of sustain electrodes, a rear dielectric layer covering the address electrodes, barrier ribs disposed on the rear dielectric layer and dividing a discharge space into discharge cells, and fluorescent layers disposed in the discharge cells. The address electrodes are connected to connection cables (not shown) disposed at upper and lower sides of the PDP.
In the PDP, in addition to the pairs of the sustain electrodes which generate a discharge, the front dielectric layer and the protective layer are formed on the rear surface of the front substrate through which visible light generated by the fluorescent layers in the discharge cells is transmitted. The transmittance of visible light is significantly reduced and the brightness of the PDP is therefore also reduced.
Furthermore, since the pairs of sustain electrodes are formed on the rear surface of the front substrate in the PDP, the majority of the sustain electrodes (i.e., the transparent electrodes, excluding the bus electrodes) must be formed of ITO, which is highly resistive, in order to allow the generated visible light to be transmitted through the front substrate. Thus, a driving voltage of the PDP increases and since the high resistance of the ITO electrodes causes a voltage drop, images cannot be uniformly displayed when the PDP is large.
In the PDP, the pairs of sustain electrodes are formed on the rear surface of the front substrate, and the discharge occurs behind the protective layer and diffuses within the discharge cells. In other words, the discharge occurs only on a portion of the discharge cells and a space in the discharge cells cannot be efficiently utilized. As a result, a driving voltage for discharging must be increased, and thus, the cost of a driving circuit, which is the most expensive piece of equipment in a PDP, increases. Furthermore, due to the concentration of the discharge in a limited space in the discharge cell, the luminous efficiency of the PDP is reduced. When the PDP is used for a long time, a charged discharge gas induces ion sputtering of the fluorescent material in the fluorescent layers due to the electric field, thereby resulting in permanent after-images.